gcc/testsuite/gcc.dg/vect/vect-reduc-sad-9.c

   1 /* Disabling epilogues until we find a better way to deal with scans.  */
   2 /* { dg-additional-options "--param vect-epilogues-nomask=0" } */
   3 /* { dg-additional-options "-msse4.2" { target { x86_64-*-* i?86-*-* } } } */
   4 /* { dg-require-effective-target vect_usad_char } */
   5
   6 #include <stdarg.h>
   7 #include "tree-vect.h"
   8
   9 #define N 64
  10
  11 unsigned char X[N] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
  12 unsigned char Y[N] __attribute__ ((__aligned__(__BIGGEST_ALIGNMENT__)));
  13 int abs (int);
  14
  15 /* Sum of absolute differences between arrays of unsigned char types.
  16    Detected as a sad pattern.
  17    Vectorized on targets that support sad for unsigned chars.  */
  18
  19 __attribute__ ((noinline)) int
  20 foo (int len, int *res2)
  21 {
  22   int i;
  23   int result = 0;
  24   int result2 = 0;
  25
  26   for (i = 0; i < len; i++)
  27     {
  28       /* Make sure we are not using an SLP reduction for this.  */
  29       result += abs (X[2*i] - Y[2*i]);
  30       result2 += abs (X[2*i + 1] - Y[2*i + 1]);
  31     }
  32
  33   *res2 = result2;
  34   return result;
  35 }
  36
  37
  38 int
  39 main (void)
  40 {
  41   int i;
  42   int sad;
  43
  44   check_vect ();
  45
  46   for (i = 0; i < N/2; i++)
  47     {
  48       X[2*i] = i;
  49       Y[2*i] = N/2 - i;
  50       X[2*i+1] = i;
  51       Y[2*i+1] = 0;
  52       __asm__ volatile ("");
  53     }
  54
  55
  56   int sad2;
  57   sad = foo (N/2, &sad2);
  58   if (sad != (N/2)*(N/4))
  59     abort ();
  60   if (sad2 != (N/2-1)*(N/2)/2)
  61     abort ();
  62
  63   return 0;
  64 }
  65
  66 /* { dg-final { scan-tree-dump "vect_recog_sad_pattern: detected" "vect" } } */
  67 /* { dg-final { scan-tree-dump-times "vectorized 1 loops" 1 "vect" } } */
  68